The player takes the role of a secret agent who must stop an evil genius, Professor Elvin Atombender, who is believed to be tampering with national security computers. The player races against the clock to reassemble and decrypt the password to Atombender's control room while avoiding deadly robots. Password pieces are found by searching furniture in the rooms. When searching, the player can also reset all moveable platforms and freeze enemy robots for a limited time. The game also features similar rewards for completing bonus puzzles. Impossible Mission enemies include two types of enemies. The first are the robots. These have a cylindrical main body. Their bodies are electrified, and some are able to use a short-range death ray. Some are stationary; others move in patterns, and others specifically hunt the player. Some have to actually see the player, and others know where the player is at all times. The second enemy is a hovering, electrified ball. Most of these chase the player. The player has six hours of game time to collect 36 puzzle pieces. Every time the player dies, 10 minutes are deducted from the total time. The puzzle pieces are assembled in groups of four. The puzzle pieces overlap so that three pieces can be assembled before the player realizes he must start over. Pieces may be in the wrong orientation, and the player may have to use the horizontal or vertical mirror images. Additionally, the puzzle pieces are randomized in every game. A completed puzzle forms a nine-letter password which lets the player reach Professor Atombender.
Development
The first element of the game to be created was the player character's animations, which designer Dennis Caswell lifted from a library book about athletics. Caswell recalled, "I animated the somersault before I had any clear idea how it would be used. I included it because the animations were there for the taking..." Caswell cites Rogue as his inspiration for the randomised room layouts, and the electronic gameSimon as his inspiration for the musical checkerboard puzzles. The hovering balls were inspired by the Rover "security guard" from the Prisoner TV series. The Commodore 64 version features early use of digitized speech: "Another visitor. Stay a while... stay forever!" and "Destroy him, my robots!" The digitized speech was provided by the company Electronic Speech Systems, who drastically raised their prices after Impossible Mission became a successful test case. Epyx did not deal with ESS again as a result. Caswell recounted: The game's title was one of the last elements to be finished. According to Caswell, "The choice of a name was delayed as long as possible, and Impossible Mission was more resorted to than chosen. It was, at least, somewhat descriptive, and the obvious allusion to was expedient, to the extent that both the game and the TV show involved high-tech intrigue."
Reception
In 1985, Zzap!64 editors ranked Impossible Mission second in their list ofthe bestCommodore 64 games, while readers ranked it first, with 26% of votes. Citing Impossible Mission as example, Compute!'s Gazette in 1986 praised Caswell as "one of those rare people who has all the skills necessary to create and design an outstanding game" while software development teams were becoming more common. COMPUTE! listed the game in May 1988 as one of "Our Favorite Games", writing that the sound effects of the character committing suicide was one of their guilty pleasures. The ZX Spectrum version was voted the 28th best game of all time in a special issue of Your Sinclairmagazine in 2004.
Legacy
The sequel, Impossible Mission II, followed in 1988. It further complicated the quest with new traps and items. Elvin's stronghold also grew in size, divided into a number of towers which the player had to traverse, all the while picking up pieces of the password. The game ElectroCop was rumored to have started as a sequel to Impossible Mission, but this has not been substantiated. In 1994, Impossible Mission 2025 was released for the Amiga. It kept the same idea as the previous games, and mainly featured updated graphics and audio, also allowing the player to choose among three different characters. The game also contains the Commodore 64 version of Impossible Mission. Developers System 3 revamped Impossible Mission for the Sony PSP, Nintendo DS and Wii. In the US, the Nintendo DS version was released exclusively at GameStop stores by Codemasters and the Wii version was released in March 2008.
